I believe once your audit database has been created and CA has been configured to write to it (along with the relevant logging levels being set), the audit data generated will remain in the database unless you decide to prune it. There used to be an Auditdb cleanup utility IBM__AUDITDBCleanup but I'm not sure if this is still present in CA 12.x.
Cheers!
MF.
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Mark Fry
Field Solutions Architect
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